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• Conclusion
• Appendices
• References
• Bibliography

CHAPTER FOUR

Conclusion

The linear electron transmission beam technique has been used to measure the total electron scattering cross sections of CH₄, NH₃, PH₃ and SiH₄ molecules. CH₄ and NH₃ cross sections were measured for 400 – 4000 eV electron energies, while SiH₄ and PH₃ cross sections were measured for 90 – 4000 eV electron energies. In a comparison of these cross sections with those measurements by other experimental groups it was revealed that the present experimental measurements are in good agreement with those produced by Garcia and Manero,^{17, 22} while total cross section measurements by Zecca et al.^{16, 21} are systematically lower than present measurements at energies higher than 1200 eV. The differences in the cross sections are likely to be caused by the poor angular resolution of the Ramsauer-type apparatus used in references [16] and [21]. Comparisons between the existing theoretical models, the present total cross sections, and the measurements by other experimental groups have shown that the Bethe-Born²⁴ approximation generally under-predicts the total cross sections. Cross sections produced in the present work are in good agreement with the empirical formula proposed by Garcia and Manero¹⁹.